This P30 Center grant proposal requests funding for a five-year period for the Center on Demography and Economics of Aging, directed by Linda Waite with Diane Lauderdale. The Chicago Center on Aging, now in its tenth year of funding from the NIA, provides support to approximately 35 funded research projects in four key areas: (1) social relationships, living arrangements, and family; (2) the social context of aging; (3) health care research; and (4) bio-behavioral pathways. We seek continued funding for three core units: (1) an Administrative and Research Support Core; (2) a Program Development Core; and (3) an External Innovative Network Core. Together these three cores facilitate and support a large and extremely active program of research and training at Chicago. Waite and Lauderdale direct the Administrative Core consisting of seven service functions: (1) proposal preparation; (2) workshops; (3) conferences; (4) computing support; (5) statistical services; (6) the Data Archive and Repository; and (7) dissemination services. Lauderdale directs the Program Development Core, which consists of an active program of pilot projects and support for new faculty development in aging. The External Innovative Network, directed by Stacy Lindau, seeks to develop a new focus on biomarkers in population-based aging research by providing a centralized resource for collecting, discussing, evaluating, and disseminating the most recent developments in the measurement and collection of biomarker and pharmaceutical data in population-based aging research. The Center aims to foster an exciting, dynamic intellectual environment for research in the demography and economics of aging; to provide research support services; to encourage the development of new research projects and research foci in the demography and economics of aging; and to facilitate collaborative research and teaching among scientists working in the field of aging research.